HI im a first year student and im only just starting out, in the examples my professor gave me he uses bcd inputs A,B,C,D to come up with a truth table standard 0-9 display, however i have been asked to use a 3 bit input to draw a truth table for a 7 segment display that spells the word BLUEFISH. how would the actual truth table to drive segments a-g look like? would it look like this?


any help is greatly appreciated

 

As an example, which segments must be lit to show "F"?

 

Hello,

Have a look at this wiki page for the segments orientation:
https://en.wikipedia.org/wiki/Seven-segment_display

Bertus

 

Welcome to AAC!

how would the actual truth table to drive segments a-g look like? would it look like this?

That's one possible implementation. If you ever have the chance of needing to display the number 8, you might choose a different combination of segments for B.

Since this is homework, you need to show your work before we can attempt to guide you to a solution

 

As an example, which segments must be lit to show "F"?

it says to Draw the truth table to drive segments (a-g) of the display. then Using the truth table you have obtained, draw Karnaugh maps for each segment to find the minimised logic expression. i can do the karnaugh maps and find the expression yet the truth table is giving me issues.
each letter of the BLUEFISH corresponds 0-7 in decimal digit.
0->’B’, 1->’L’, 2 ->’u’, 3-> ‘E’, 4->’F’, 5->’i’, 6->’S’, 7->’h
so digit 0 needs all segments lit to produce B and so on.

from that i produced the table in my original post, with it being 3 bit input would i be correct in assuming that i only do a,b,c and not the standard 4 bit BCD a,b,c,d.
i know that B can be shown in an alternative format however i have been asked to do so as shown in the image

 

Hello,

The give table is not complete.
I would use the leading zeros too.
You could do this by placing A, B and C in separate coloms.

Bertus

 

each letter of the BLUEFISH corresponds 0-7 in decimal digit.
0->’B’, 1->’L’, 2 ->’u’, 3-> ‘E’, 4->’F’, 5->’i’, 6->’S’, 7->’h

You didn't state that requirement in the first post. It would be helpful if you posted the complete text for the problem.

 

You have seven different logic problems. You have one logic for each segment. Treat them as separate 3-input, 1-output logic problems. Don't make it harder than it is.

 

You have seven different logic problems. You have one logic for each segment. Treat them as separate 3-input, 1-output logic problems. Don't make it harder than it is.

thanks i think i get it now thankyou all for the help

 

Wouldn't it look better in All Caps?